A very large number of products are offered for sale in containers having a neck the opening of which is provided with a sealing foil made of aluminum or aluminum-plastics material composite, for example an aluminum-polyethylene; this foil is welded or glued to a bonding material which is previously laid on top of the container neck when the container is in glass, in porcelain, or even in some types of synthetic materials such as melamines.
Thus, it is necessary to first of all deposit an adhesive material on top of the neck, then to provide a sealing pellet, to weld or fix in any other way this sealing pellet by application of heat in order to set the glue, or by application of a high frequency current or still by using any other means appropriate for the products in contact, and thereafter a lid has to be put in position on the neck.
The hereabove operations are rendered particularly complex since it is necessary to work in a sterile atmosphere, and most often even in a vacuum chamber.
There is thus used complex installations which are commercially interesting only for the manufacture of products in very large quantities as this is the case for example for the conditioning of pots for lyophilized products such as coffees.
The above mentioned complex installations cannot be suitably used when only small series of containers have to be conditioned, since the cost price and therefore the marketing price of the products would be considerably increased.
The invention solves the problem exposed hereabove by providing a new tight closing device.